B.
Tech II Year II Sem- CSE
Data Base Management Systems
Unit II
Multiple choice Questions
I. Choose the correct alternative:
1) introduced the relational model.
A) Atul kahate B)James Gossling C) EF Codd D)Dennies Rithchie [ C ]
2) refers to the number of tuples in a relation(Table)
A) Entity B)Column C) Cardinality D)None of the above [ C ]
3) refers to the number of attributes in a relation(Table)
A) Degree B)Row C)Column D)All of the above [ A ]
4) In , there are a set of possible atomic values that apply to an attribute.
A) Attribute B)Instance C)Domain D)Schema [ C ]
5) The indicates the name of each relationship and all of its columns and
attributes.
A) Relational Instance B)Relational Keys C)Relational Schema D)Relational Database[ C ]
6) To include integrity constraint in an existing relation use :
A) Create table B) Modify table C) Alter table D) Drop table [ C ]
7). A query in the tuple relational calculus is expressed as:
A) {t | P() | t} B) {P(t) | t } C) {t | P(t)} D) All of the mentioned [ C ]
8) Inorder to ensure that the value of budget is non-negative which of the following should
be used?
A) Check(budget>0) B) Check(budget<0) C) Alter(budget>0) D) Alter(budget<0) [ A ]
9) Foreign key is the one in which the of one relation is referenced in another
relation.
A) Foreign key B) Primary key C) References D) Check constraint [ B ]
10) Domain constraints, functional dependency and referential integrity are special forms of
A) Foreign key B) Primary key C) Assertion D) Referential constraint [ C ]
11) Which of the following commands do we use to delete a relation (R) from a database?
A) drop table R B) drop relation R C) delete table R D) delete from R [ A ]
12. Which of the following command is a type of Data Definition language command
A) Create B)Update C)Delete D)Merge [ A ]
13. The entity set person is classified as student and employee. This process is called
A) Generalization B) Specialization C) Inheritance D) Constraint generalization [ B ]
14) Which relationship is used to represent a specialization entity?
A) ISA B) AIS C) ONIS D) WHOIS [ A ]
15) Relational Algebra is a query language that takes two relations as input and
produces another relation as an output of the query.
A) Relational B) Structural C) Procedural D) Fundamental [ C ]
II . FILL IN THE BLANKS
1. The truncate statement in SQL removes all data from the table and free the table's space
2. Foreign key is used to represents the relationships between the tables(relations)?
3. Sigma (Greek) symbol is used to denote the selection operation in relational algebra?
4. Integrity constraints ensure that changes (update deletion, insertion) made to the
database by authorized users do not result in a loss of data consistency.
5. A candidate key is an attribute or set of attributes that can uniquely identify a tuple.
6. Drop command is used for removing (or deleting) a relation from the SQL database
7. Delete command is used to delete the existing row in a table.
8. The primary key is a set of one or more of these attributes to uniquely identify a record in
the table
9. Expand DDL Data Definition Language
10. Manipulating data in a database such as inserting, updating, deleting is defined as
Data Manipulation Language
11. A Candidate key is a minimal super key
12. The relational model uses a collection of tables to represent both data and the
relationships among those data.
13. In the logical-design phase, the designer maps the high-level conceptual schema onto the
implementation data model of the database system.
14. A Relational Calculus system is a non-procedural query language.
15. In a relation, tuples are selected using the tuple relational calculus.
